U0139high severityNetwork
Lost Communication With Shift-By-Wire Module B
on 2009 Audi Q7 3.0L Supercharged V6 · AWD
What this code means
Communication with the shift-by-wire module B has been lost on the network. This may prevent proper gear selection.
Symptoms
- Unable to select gears
- Shifter warning message
- Vehicle stuck in park or gear
Common causes
- Damaged bus wiring or connectors
- Poor ground or power supply
- Failed shift-by-wire module
- Blown fuse
Diagnostic steps
- Scan modules for communication codes
- Verify module power and ground
- Inspect CAN wiring and connectors
- Check bus signal integrity
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Other Network codes on this vehicle
00003
Control Module - Defective
01304
Radio - No Communication
01312
Powertrain Data Bus - Defective
01314
Engine Control Module (ECM) - no communications
01315
Transmission Control Module (TCM) - No Communication
01316
ABS Control Module - No Communication
01317
Instrument Cluster Control Module (J285) - No Communication
01318
Immobilizer Control Module - No Communication
01321
Airbag Control Module - No Communication
U0001
High Speed CAN Communication Bus